Open AccessUltra-sensitive refractive index sensor using CMOS plasmonic transducers on silicon photonic interferometric platform
Author(s) -
Athanasios Manolis,
E. Chatzianagnostou,
George Dabos,
Dimitra Ketzaki,
Bartos Chmielak,
Anna Lena Giesecke,
Caroline Porschatis,
Piotr Cegielski,
Stephan Suckow,
Laurent Markey,
Jean-Claude Weeber,
Alain Dereux,
Stefan Schrittwieser,
R. Heer,
Nikos Pleros,
D. Tsiokos
Publication year - 2020
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.383435
Subject(s) - materials science , interferometry , extinction ratio , silicon photonics , refractive index , photonics , mach–zehnder interferometer , optoelectronics , sensitivity (control systems) , cmos , plasmon , context (archaeology) , transducer , waveguide , optics , electronic engineering , electrical engineering , physics , engineering , wavelength , paleontology , biology
Optical refractive-index sensors exploiting selective co-integration of plasmonics with silicon photonics has emerged as an attractive technology for biosensing applications that can unleash unprecedented performance breakthroughs that reaps the benefits of both technologies. However, towards this direction, a major challenge remains their integration using exclusively CMOS-compatible materials. In this context, herein, we demonstrate, for the first time to our knowledge, a CMOS-compatible plasmo-photonic Mach-Zehnder-interferometer (MZI) based on aluminum and Si3N4 waveguides, exhibiting record-high bulk sensitivity of 4764 nm/RIU with clear potential to scale up the bulk sensitivity values by properly engineering the design parameters of the MZI. The proposed sensor is composed of Si3N4 waveguides butt-coupled with an aluminum stripe in one branch to realize the sensing transducer. The reference arm is built by Si3N4 waveguides, incorporating a thermo-optic phase shifter followed by an MZI-based variable optical attenuation stage to maximize extinction ratio up to 38 dB, hence optimizing the overall sensing performance. The proposed sensor exhibits the highest bulk sensitivity among all plasmo-photonic counterparts, while complying with CMOS manufacturing standards, enabling volume manufacturing.